Browser anonymization functions compared

Setting Boundaries

Firefox developers have equipped the browser with a completion feature for forms; it stores 10 values by default. Users can disable this function completely in the configuration dialog if needed. This is also where you can tell Konqueror to send do-not-track messages. On request, the KDE browser draws a frame around incompletely loaded images and prevents automatic reloading of pages and redirection to other websites. An ad filter blocks URLs that are on a blacklist. Users can maintain a blacklist themselves or reference a list on the web.

Konqueror only accepts cookies signed by the server, but it can also reject cookies completely, prompt the user, and delete cookies on exiting. Session cookies are blocked separately for selected pages; exceptions are allowed. Cookies are managed so that stored data is grouped neatly by domain name; a search box helps locate a candidate. Just one click lets you view all the data for a cookie; however, users can only delete a single cookie, or all at once.

Users can disable JavaScript either globally or specifically for individual sites; when opening pop-ups, Konqueror asks for permission, on request. Konqueror was the only browser in the test that enabled Java from the outset. Exceptions for individual sites are possible. If executing a Java application is allowed, the browser switches on a safety manager to at least prevent direct access to the system. Konqueror also shuts down Java applications that run too long – again, the user can define the period of time to wait.

In the somewhat rudimentary extension management feature, users can switch extensions on and off and set up special rules. During operation, Konqueror also alternates between the KHTML and WebKit engines, and the spell checker relies exclusively on local dictionaries. The browser cannot delete web storage and loads web fonts as a matter of principle. It does not have a geolocation API or a privacy mode.

Fear of Persecution

The default state of all the test candidates is frightening. To surf fairly anonymously, users themselves have to work their way through a jungle of setup dialogs. Even if you have defined all possible restrictions, the browser will still readily reveal a huge amount of information, and privacy mode does not earn that name in any of the programs: In general, the browsers simply delete all data on exit. Some browsers can camouflage the underlying technologies or rename them.

Chrome turned out to be particularly talkative. It is difficult to stop it from phoning home. Epiphany lags behind the competition; with so few configuration options, users will find it difficult to keep the browser quiet.

Although Firefox offers much more in the settings dialogs, it does not impress with its clarity. On the plus side, Firefox does have thousands of add-ons that help harden the browser. Konqueror in particular lacks particular settings for newer web technologies, such as web storage.

Users who want to surf anonymously, should resort to Firefox and spend some time setting it up with native features and installing anonymizing add-ons.